Weather (theme 2) Flashcards
What causes wind
Differences in air pressure
What happens when there are different air pressures
Air moves from an area of high pressure to an area of low pressure the greater difference in air pressure the stronger the winds
How is sun’s energy spread at the poles
Spread over large area resulting in low temps and high pressure
How is sun’s energy spread at the equator
Concentrated in a small area resulting in high temps and low pressure
3 convection cells
Hadley ferrel polar
7 stages of global atmospheric circulation
- Warm air rises from equator creating belt of low pressure as air rises it cools
- Condensation creates clouds and rain that move north and south of the equator
- At 30 North and south cold dry air skins creating high pressure and clear skies
4.when sinking air reaches earth’s surface ut noves either back to equator or towards poles
- At 60 North south equator surface air meets Colfer air from the piles which rises creating a bley of low pressure
- air rises and colds moves back yo equator or towards the poles
- At piles coil air skins so highn pressure and moves back to equator
What is an air mass
large pocket of air in the atmosphere
What air masses affect the uk?
Polar maritime
Arctic maritime
Polar continental
Tropical Maritime
Tropican continental
Types of surface winds
Trade winds, westerlies
What are trade winds
30 degrees north/south back towards the equator
winds from the northern and southern hemisphere meet at the equator and are heated
What are westerlies
30 degrees north to the north pole and south to the south pole
What are surface winds
At 30o north and south, the air from the equator cools and falls. When the cool air reaches the Earth’s surface, surface winds blow the cool air either towards the equator, or away from the equator towards the Poles.
Features of arid climate zones
Temperatures are high and rainfall is low for most of the year in arid (dry) regions.
Rainfall is low because of a high pressure belt caused by sinking air from 2 cells meeting at about 30o north and south of the equator.
Features of temperate climate zones
Temperate regions experience moderate summers and winters.
Rainfall is frequent because of a low pressure belt caused by rising air from 2 cells meeting at about 60o north and south of the equator.
Features of tropical climate zones
Temperatures and rainfall are high throughout the year in tropical regions.
Rainfall is frequent because of a low pressure belt caused by rising air from 2 cells meeting near the equator.
Features of Polar climate zones
Temperatures are low throughout the year in polar regions.
Factors that affect climate
Latitude
Altitude
Distance from sea
Global atmospheric circulation
How does latitude affect climate
-Affects how much sun a place gets and how strong it is in different seasons
-Further away from the equator cooler
-Closer to the poles sunlight has a larger area of atmosphere to pass through so more energy is lost so cooler
How does Air pressure affect climate?
-Areas of low pressure develop clouds and precpitation while high pressure brings clear sunny weather
How does global atmospheric circulation affect climate?
The Earth’s atmosphere is split into a
number of cells. Each cell is either high
or low pressure. Depending on the type
of pressure the air will either be rising
or sinking.
The Ferrell Cell meets the Polar Cell at
around the same latitude as the UK.
Here warm moist air will meet cool dry
air this leads to a low pressure weather
system where there will be poor
weather e.g. rain and wind.
The Jetstream can make this weather
better or worse.
How does altitude affect climate?
Altitude is the height above sea
level
Locations at a higher altitude
have colder temperatures.
Temperature usually decreases
by 1°C for every 100 metres in
altitude.
In the mountainous areas of the
UK the weather will be cooler
than at sea level.